package io.github.dunwu.javacore.collection;

import java.util.Iterator;
import java.util.TreeMap;

public class TreeMapDemo {

	private static final String[] chars = "A B C D E F G H I J K L M N O P Q R S T U V W X Y Z".split(" ");

	public static void main(String[] args) {
		TreeMap<Integer, String> treeMap = new TreeMap<>();
		for (int i = 0; i < chars.length; i++) {
			treeMap.put(i, chars[i]);
		}
		System.out.println(treeMap);
		Integer low = treeMap.firstKey();
		Integer high = treeMap.lastKey();
		System.out.println(low);
		System.out.println(high);
		Iterator<Integer> it = treeMap.keySet().iterator();
		for (int i = 0; i <= 6; i++) {
			if (i == 3) {
				low = it.next();
			}
			if (i == 6) {
				high = it.next();
			} else {
				it.next();
			}
		}
		System.out.println(low);
		System.out.println(high);
		System.out.println(treeMap.subMap(low, high));
		System.out.println(treeMap.headMap(high));
		System.out.println(treeMap.tailMap(low));
	}

}
